THEORIES AND CONCLUSIONS 235 
Cuckoo. But to argue from such observations that 
there are more males than females is false logic. 
I do not pretend to have enough evidence to 
prove or disprove the statement ; but I contribute 
an observation of my own which may be significant. 
In the season of 1921 there were proved to be at 
least nine female Cuckoos laying along the direct 
line between my original common, the territory 
of Cuckoo A, and the second one which is dealt 
with in Chap. IX, a distance of some three miles. 
Some of these hen Cuckoos were parasitic upon 
Hedge-sparrows, and possibly other species. Yet 
a male Cuckoo, which we were able to identify 
unmistakably by a peculiarity in his voice, 
regularly traversed the whole distance and ap- 
peared to be equally at home at one end as at the 
other. 
Do the males outnumber the females ? Is the 
Cuckoo polyandrous ? If so — if a hen has several 
male partners — are they all members of the same 
type of Cuckoo ? Such questions may be multi- 
plied endlessly. My own impression- — I will not 
put it higher — is that the Cuckoo is probably 
promiscuous, i.e. both polyandrous and polygamous. 
I see no reason to assume that one sex outnumbers 
the other, and the balance of evidence is against 
